TW200904268A - Metal foil plated laminated board and printed wiring board - Google Patents

Abstract

Provided is a metal foil plated laminated board. A fiber base material is a glass cloth having a thickness of 50 μm or less.A metal foil with resin is provided with a metal foil and a resin layer composed of a resin composition which is formed on the metal foil and cures with heat. The fiber base material and a pair of such metal foils are arranged to bring the resin layers into contact with the fiber base material, and are integrated by applying heat and pressure to form the metal foil plated laminated board.

Description

200904268 IX. Description of the Invention [Technical Field] The present invention relates to a metal foil-clad laminate and a printed wiring board. [Prior Art] A laminate for a printed wiring board is obtained by superposing a prepreg having a resin composition having electrical insulating properties as a matrix with a predetermined number of sheets and heating and pressurizing. Further, when the production of a printed wiring board is formed by a subtractive method, a metal foil-clad laminate is used. The metal foil-clad laminate is formed by laminating a metal foil such as a copper foil on the surface (single or both surfaces) of the prepreg, and is produced by heating and pressurizing. As the electrically insulating resin, a thermosetting resin such as a phenol resin, an epoxy resin, a polyimide resin, or a bismaleimide-triazine resin is widely used. Further, a thermoplastic resin such as a fluororesin or a polyphenylene ether resin can also be used. On the other hand, "the spread of information terminal devices such as personal computers and mobile phones" has been progressing toward miniaturization and high density. In fact, the mounting form is a pattern of the surface array type which is represented by a BGA (ball grid array) which uses a plastic substrate from the pin insertion type to the surface mounting type. In the case of directly encapsulating a substrate such as a bare chip of the BGA, the connection between the wafer and the substrate is generally performed by wire bonding by thermal ultrasonic compression. Therefore, the substrate on which the bare wafer is packaged becomes exposed to a high temperature of 150 ° C or higher, and the resin must have a certain degree of heat resistance. Furthermore, in such a substrate, there is also a wafer in which the package is taken out once, and -4-200904268 requires repairability. In this case, the same degree of heat is applied, and then the substrate is again subjected to a crystal heat treatment. Therefore, in the case of a substrate requiring repairability, the ring has thermal shock resistance. Therefore, there is a case where peeling occurs between the conventional insulation and the resin. Therefore, in the printed circuit board, in order to improve the resistance, the crack resistance, and the fine line formation property, the resin which is contaminated with polyamido ruthenium as an essential component is referred to, for example, Patent Document η. In addition, there is a heat-resistant substrate of a fiber base material which is formed of a polyimide resin and a thermosetting resin (see, for example, Patent Document 1: JP-A-2003-5 5486 - 1 93 1 3 9 [Invention] The problem to be solved by the invention is accompanied by the thinning of the printed wiring board, the fiber substrate, the glass cloth having a thickness of about 10 μm is supplied, and the resin composition is so thin. a fiber base material or a metal foil-clad laminate. However, the use of a resin layer thin on one side of the fiber base material is likely to be different from the thickness present. The thickness of the resin layer produces a metal foil-clad laminate obtained in the table, and It is easy to cause warpage when it is carried out on a circuit board. The metal is applied to the chip package during chip packaging, and the resin is also required to be subjected to high temperature. The fiber substrate is thermally impacted and resistant to reflow. The prepreg of the immersion composition (in the case of the oxime resin-modified resin composition immersed in the literature 2). The report material also developed a thinner basis for the fiber substrate. Thus, the development of a thinner prepreg prepreg When there is a difference in the back side of the resin layer on the opposite side, the warpage of the printed line foil laminate after the road processing ' -5- 200904268 is easy to reduce the circuit formability during circuit processing. Reduced mounting performance and reduced reliability. Moreover, with the miniaturization and high performance of electronic equipment, it is necessary to collect printed circuit boards in which parts are packaged in a limited space. Therefore, multiple printed circuit boards are connected in multiple stages and connected to each other. And a flexible circuit board connection method, and a hard-flexible substrate in which a flexible substrate based on polyimide and a conventional hard substrate is multilayered, so that the electronic device is miniaturized and high. In view of the performance, it is desired to develop a printed wiring board which can be bent at will. Therefore, the present invention provides a metal foil-clad laminate which can produce a printed wiring board which is excellent in heat resistance, sufficiently reduces warpage, and can be bent at will, and uses The present invention provides a metal foil-clad laminate which will have 5 Ομηι a resin-coated metal foil of a glass cloth of a thickness and a resin layer provided with a metal foil and a resin composition formed by heating on the metal foil, and a resin The layer is bonded to the fiber substrate, and is heated and pressurized to form an integrated product. The present invention further provides a metal foil-clad laminate which is a fiber substrate of glass cloth having a thickness of 5 Ομηι or less. a resin film obtained by a resin composition which is disposed on both sides of the fiber base material and is cured by heating, and a metal film disposed on a side opposite to the fiber substrate of the resin film of -6-200904268 The foil is heated and pressed to form such a metal-clad laminate, which has a very high heat resistance and warpage, and can be formed by coating a metal foil laminate of a printed circuit board which can be bent at any time, thereby obtaining such an effect. However, the present inventors considered the following reasons. In the metal foil-clad laminate of the present invention, it is not necessary to use a prepreg which is a resin composition. That is, in the present invention, the metal foil can be directly integrated via the resin composition, and the foil can be laminated. Therefore, it is considered that the thickness of the cured layer formed by the hardened material existing on both sides of the fibrous base material is hardly deteriorated. Further, it is considered that the metal foil-clad laminate of the present invention can be arbitrarily bent as a printed wiring board by providing a fiber base material having a thickness of 50 μm or less. The thickness of the resin-coated layer of the metal foil-clad laminate and the thickness of the resin film are 30 to 70 μm. The metal foil-clad laminate is provided with the material and the resin embedded in the fiber substrate. a hardened base material layer of the composition, a laminate of a cured layer of one of the resin groups obtained by sandwiching the resin substrate of the fibrous base material layer, and a metal foil laminated plate of a metal foil sandwiched with a set of Among them, the difference in the average thickness of one set is preferably 10% or less of the average thickness of the cured layer of one set. Thereby, the present invention for reducing warpage can be further and surely exerted. Further, when the resin composition contains a thermosetting resin, it is obtained. Fully reduced. Although the present invention is not completely finished, the base material for impregnating the base material is made of a metal-clad resin composition, and the glass cloth which is difficult to produce is excellent in flexibility, and the above-mentioned tree is preferable. The effect of curing the fiber obtained from the fiber substrate as a result of the total thickness of the cured product of the laminate is preferable because the heat resistance is better than 200904268. When the thermosetting resin is an epoxy resin, it is preferable because it can improve heat resistance and insulation. Further, when the resin composition contains an acrylic resin, a resin composition having better heat resistance and flexibility can be obtained, and the bending property of the printed circuit board can be improved, which is preferable. When the resin composition contains a polyamide amide resin, the bonding property between the metal layer or the circuit and the insulating layer is higher, and the insulating layer can obtain higher heat resistance. Further, the present invention provides a printed wiring board obtained by forming a wiring pattern on the above-mentioned metal foil-clad laminate. Such a printed wiring board can be bent at will because it has small warpage and good flexibility. Advantageous Effects of Invention According to the present invention, it is possible to provide a metal foil-clad laminate which can produce a printed wiring board which is excellent in heat resistance, sufficiently reduces warpage, and which can be bent at will, and a printed wiring board using the same. [Embodiment] Hereinafter, preferred embodiments of the present invention will be described in detail while referring to the drawings. In the drawings, the same components are denoted by the same reference numerals, and the description thereof will not be repeated. Further, the positional relationship such as "upper, lower, left, and right, is not particularly limited" based on the positional relationship shown on the drawing. Further, the size ratio of the drawing is not limited to the ratio shown. Further, Γ (meth) acrylate in the present specification means "acrylate" and "methacrylate" corresponding thereto. Similarly, "(meth)acrylic" means "acrylic acid" and "methacrylic acid" corresponding to its -8-200904268 [metal-clad laminate] FIG. 1 is a view showing a metal coating according to a preferred embodiment of the present invention. A cross-sectional view of a model of a foil laminate. The metal foil-clad laminate 200 shown in Fig. 1 is provided with a laminate 30 and a tantalum laminate 30, and is provided on both sides of the laminate 30. The laminate 30 is composed of a fibrous base material and a fibrous base material layer 4 obtained by embedding a resin composition embedded in a fibrous base material, and cured layers 1 and 2 of a resin composition sandwiched therebetween. The metal foil-clad laminate 200 may be a resin-attached metal foil of a resin substrate obtained by a fiber substrate and a resin composition obtained by heating a metal foil and a resin composition formed by heating on the metal foil. The layer is bonded to the fiber base material, and is obtained by heating and pressurizing to form an integrated method. At this time, a part of the resin composition is embedded and hardened in the fiber base material to form a laminate 30 composed of the cured material layers 1 and 2 of the resin base material layer 4 and the resin composition of the crucible. . Further, the metal foil-clad laminate 200 may be a resin film obtained by laminating a fiber base material with a resin composition which is disposed on both sides of the fiber base material and cured by heating, and may be disposed on the resin film. The fiber substrate is obtained by a method in which a metal case of one of the opposite sides is formed by heating and pressurization. At this time, a part of the resin composition is embedded and hardened in the fiber base material, and the laminate 30 formed of the cured product layers 1 and 2 of the resin base material layer 4 and the resin composition of the crucible is formed. . Hereinafter, the fiber base material constituting the metal foil-clad laminate 200, the tree 200904268 fat composition, and the metal foil will be described. (Fiber base material) The fiber base material is a glass cloth having a thickness of 5 μm or less. With such a fiber base material, it is possible to bend the circuit board with flexibility. At the same time, dimensional changes such as temperature and moisture absorption accompanying the manufacturing steps can be made small. The thickness of the fiber base material is preferably 30 μm or less, and 30 μm or less, from the viewpoint of making the metal foil-clad laminate 200 printed wiring board thinner and imparting good flexibility. The thickness of the fibrous substrate is particularly limited, usually to the extent of 1 〇 μηη. A glass cloth having a thickness of 50 μm or less is obtained, for example, from the market of WEX1037 and WEX1015 (the above is manufactured by Asahi SYUeBEL Co., Ltd.). (Resin composition) The resin composition is required to be heat-resistant from the production of a printed wiring board. It is preferred to contain a thermosetting resin. The thermosetting resin forms an insulating cured product via addition. The thermosetting resin is preferably a thermosetting resin having a crosslinking. Such thermosetting properties are epoxy resin, polyimide resin, unsaturated polyester resin, fat, bismaleimide resin, triazine-bismaleimide-tree resin. These can be used individually or in combination of 2 or more types. The thermosetting resin is a resin having a glycidyl group. By printing the fold, the substrate, which will be described later, is the lower limit of the WEX 1 027 sale, and the heat-bonded functional resin is cured by heat. For example, the polyurethane resin and the phenol are used as the ring-10. - 200904268 Oxygen resin is more ideal. The heat, mechanical, and electrical properties of the cured product formed by hardening the resin composition at a temperature of 18 ° C or lower by using an epoxy resin are particularly excellent. The epoxy resin is preferably one having two or more glycidyl groups. The more the number of glycidyl groups, the better, and more than three are more desirable. Specific examples of the epoxy resin include polyvalent phenols such as bisphenol A, phenol resin phenol resin, and o-cresol novolac type phenol resin, and polyvalent alcohols such as 1,4-butanediol and epichlorohydrin ( Epichlorohydrin; a polyglycidyl ether obtained by the reaction; a polyglycidyl ester obtained by reacting a polyprotonic acid such as capric acid or hexahydrophthalic acid with epichlorohydrin; an amine, a guanamine or a compound having a heterocyclic nitrogen salt group; N-glycidyl derivative; alicyclic epoxy resin. In the case of using an epoxy resin, it is preferred to use a combination of a hardener. Moreover, a hardening accelerator can also be used. The more the number of glycidyl groups which the epoxy resin has, the less the amount of the hardener and the hardening accelerator can be formulated. The hardener and the hardening accelerator of the epoxy resin can be used as long as they are reactive with the epoxy resin or can promote the curing of the epoxy resin, and are not limited. As the curing agent and the curing accelerator, for example, an amine, an imidazole, a polyfunctional phenol or an acid anhydride can be used. Examples of the amine include diamine diamine, diaminodiphenylmethane, guanyl urea, and the like. Examples of the polyfunctional phenols include hydroquinone, resorcin, bisphenol A, and halides thereof, such as a phenol resin type phenol resin and a cresol type phenol resin which are condensed with formaldehyde. Examples of the acid anhydride include phthalic anhydride 'diphenyl ketone tetracarboxylic dianhydride and methyl hymic acid (methylhymic acid). Ampicoids are preferred as hardening accelerators, such as alkyl substituted imidazoles, benzimidazoles. -11 - 200904268 The amount of hardener and hardening accelerator is similar to the epoxy equivalent of epoxy resin in the case of amines. It is a hardening accelerator, not simply The amount of the active amount is preferably 0 parts by mass for the epoxy resin 300 parts by mass. In the case of a polyfunctional phenol or an acid anhydride, the phenolic hydroxyl group or carboxyl group is 0.6 to 1.2 equivalents per equivalent of the resin. When the amount of the hardener or the hardening accelerator is too small, the unhardened resin remains, and the Tg (glass transition temperature) tends to be low, and too much unreacted hardener or hardening accelerator remains, and the insulating property of the cured product tends to be low. . Further, the resin composition is a resin component which can contain a high molecular weight in order to improve flexibility and heat resistance. As such a high molecular weight component, for example, an acrylic resin and a polyamidoximine resin. As the acrylic resin, a polymer obtained by separately polymerizing acrylic acid, methacrylonitrile, a glycidyl group-containing (meth)acrylic compound, or the like, or a molecular copolymer of these plural copolymerized olefinic resins can be used. It is stipulated that the average weight of the converted standard polystyrene obtained by GP C (gel permeation analyzer) is 300,000 to 1,000,000, and more preferably 400,000 to 800,000. Furthermore, GPC was measured by using three directly connected "GMH XL" (manufactured by Tosoh Corporation, trade name) as a measuring column and using THF furan as a solvent. As the resin composition, it is preferred to use a suitable addition of a fat, a curing agent, a curing accelerator or the like to these acrylic resins. Moreover, as a living of propylamine. When the 001 to 10 0 of the hydrogen is preferred to the epoxy, the resin and the monomer of the acrylic resin are reduced. The amount of the acrylonitrile layer is, at this time, ^ Tosoh (tetrahydro epoxide tree-12-200904268 grease, for example, commercially available product can be obtained HTR-860-P3 (Nagase Chemtex, manufactured by Nagase Chemical Co., Ltd., trade name , weight average molecular weight: 850,000), HM6-1M50 (manufactured by Nagase Chemtex Chemical Co., Ltd., trade name, weight average molecular weight: 500,000). As a polyamidoximine resin, it is a helium oxide structure. The alkane-modified polyamidoximine is preferred. The oxime-modified polyamidoximine may have a mixture of an aromatic diamine having two or more aromatic rings and a decyl diamine, and a benzene. The step of reacting tricarboxylic anhydride to form a dimercaptodiamine dicarboxylic acid and the step of reacting a dimercaptodiamine dicarboxylic acid with a diisocyanate to form a mercaptoamine group to obtain a polyamidoquinone imine. A ruthenium imine resin, which has more than 10 guanamine-based polyamidoximine resins in one molecule, that is, a polyamidoximine having more than one guanamine group. Molecules, containing 70% by mole to 100% by mole, can improve mechanical strength The viewpoint of heat resistance and flexibility is preferable. On the other hand, when the molecular weight of the polyamidoximine containing 10 or more guanamine groups in one molecule is less than 7 〇 mol%, the flexibility tends to decrease. .

The content ratio (range) of the polyamidoximine resin containing one or more sulfhydryl groups in one molecule, the chromatogram obtained from the GPC of the entire amount of the polyamidoximine resin, and the other obtained The number of guanamine groups per unit weight (in terms of the number of moles). For example, from the molar number (A) of the guanamine group contained in the polyamidoximine (X) g, the molecular weight of the polyamidoquinone imine containing 10 guanamine groups in one molecule is calculated (C=l 〇XX/A). Then, the chromatogram obtained by GPC of the entire amount of the polyamidoximine resin is determined by the ratio of the number average molecular weight of the entire region (area) to (C - 13 - 200904268 ) or more ( The area) can be determined as a content ratio of a polyamidoximine containing 1 amino group in one molecule. As a result, the area (area) in which the number average is divided into (C) is 70% to 100%. It is a quantitative method for the guanamine group, and NMR, 1R, hydroxylamine _ color reaction method, N-bromine 可 can be used. Amine method. In the measurement of the above-mentioned GPC, "GL-S300MDT-5" (trade name of Hitachi Chemical Co., Ltd.), which is directly connected, is used as a measuring column, and DMF (dimethylformamide) containing 0.60 M phosphoric acid and 0 lithium bromide is used. THF (volume ratio: 1/1 solution is used as a solvent. The ratio of amidoxime-modified polyamidoquinone imine, aromatic diamine a to decanediamine b (a/b), in moles The ratio is 99.9/0.1 ~0/1 00 is more ideal than '95/5~30/70, and 90/10~40/60 is more ideal. When the mixing ratio of oxime b is too much, τ g tends to decrease. When too little, the organic solvent (varnish solvent) used for the preparation of the varnish of the composition tends to remain in the resin layer of the resin-attached metal foil or the resin film c as an aromatic diamine, for example, 2, 2 _ double [4 - (4-Aminophenoxy)propene (BAPP), bis[4-(3-aminophenoxy)phenyl]indole[4-(4-aminophenoxy)phenyl]indole 2,2_bis[4-(4-aminophenyl)phenyl]hexafluoropropane, bis-aminophenoxy)phenyl]methyl 4,4'-bis(4-aminophenoxy) Biphenyl, bis[4-(4-aminophenoxy)ether, bis[4-(4-aminophenoxy)phenyl]one 1,3_bis(4-_oxy)benzene, 1,4-bis(4-aminophenoxy)benzene, 2,2,-xylene-4,4'-diamine, 2,2' - bis(trifluoromethyl)biphenyl_4,4'-dioxa-2,6,2',6'-tetramethyl-4,4,diamine, 5,5,_dimethyl-2 2, _ sulphur 醯 醯 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0联-14- 200904268 Benzene-4,4'-diamine, 3,3'-dihydroxybiphenyl-4,4'-diamine, (4,4'-diamino)diphenyl ether, (4, 4'-Diamino)diphenylhydrazine, (4,4'-diamino)diphenyl ketone, (3,3'-diamino)diphenyl ketone, (4,4'-diamino group) Diphenylmethane, (4,4'-diamino)diphenyl ether, (3,3'-diamino)diphenyl ether. As the alkoxyalkylene diamine, for example, the oxime diamine represented by the following general formula (3), (4), (5) or (6). In these formulas, η or m represent independent positive integers. Mi

3 ο 3 Η卜Η C1SIC

(3) h2nch2ch2ch2 [2] (4) c6h5 H2NCH2CH2CH2-hSi-〇- c6h5 •Si—CH2CH2CH2NH2 c6h5

3 C 3 Η卜Η C1SIC [化4]

5) /(V H2NCH2CH2CH2

Ch3 \ ch3

Si—〇4—Si—CH2CH2CH2NH2 (6) CH3/n CH3 -15- 200904268 As the above-mentioned general formula (3), the oxirane February: 22-161AS (amine equivalent 450), X-22-161A ( The amine equivalent is 22-161B (amine equivalent of 1 500) (the above is Shin-Etsu Chemical, BY16-853 (amine equivalent 650), BY16-853B (amine 1 (above is TORAY Toray Dow Corning). As (6) The alkoxydiamine represented by the formula, for example, X-22-9409 ( ), X-22-1660B-3 (amine equivalent: 2200) (the above is manufactured by Shinsei Co., Ltd.). As the diamine, an aliphatic diamine can also be used. The lipid is, for example, a compound represented by the following general formula (7): [Chemical Formula 5] ^, for example, X-840), manufactured by X-Industry Co., Ltd.) I Amount 2200) The above general formula amine equivalent of 700 chemical industrial aliphatic diamine,

In the formula (7), X represents a methylene group, a sulfonyl group or an ether single bond, and R1 and R2 each represent a hydrogen atom independently a substituent of the alkyl group, and P represents an integer of 1 to 50. As R1], an alkyl group having 1 to 3 carbon atoms is preferable as a phenyl group, for example, an alkyl group having 1 carbon number or a halogen atom. From the viewpoint of low modulus of elasticity and from the viewpoint of X, an ether group is preferred. As such an aliphatic Jafamine D-400 (amine equivalent 400), Jafamine D- amount 1 000 ). a diisocyanate which is reacted with a diimine dicarboxylic acid, an alkyl group, a pseudo group or a substituent which may also have an alkyl group of R 2 , a high Tg coexisting with an amine such as 2000 (amine as described below generally -16-200904268 Formula (8): 0CN-R3-NC0 (8) In the formula (8), R3 represents a divalent organic group or a divalent aliphatic hydrocarbon group having at least one aromatic ring. R3 is a divalent organic organic group having an aromatic ring. When the diisocyanate is an aromatic diisocyanate and R3 is a divalent aliphatic hydrocarbon group, the diisocyanate is an aliphatic diisocyanate. It is preferred to use an aromatic diisocyanate as the diisocyanate. In this case, the aromatic diisocyanate and The aliphatic diisocyanate is more preferably used. As the divalent organic group having an aromatic ring, a group represented by -C6h4_Ch2-C6H4-, a tolyl group and an extended naphthyl group are preferable. As a divalent aliphatic hydrocarbon group, it is a six-membered aliphatic group. Methyl, 2,2,4-trimethylhexamethylene and isophorone are preferred. As the aromatic diisocyanate, for example, 4,4'-diphenylmethane diisocyanate (MDI), 2,4 - Toluene diisocyanate, toluene 2,6-diisocyanate , naphthalene-1,5-diisocyanate, 2,4-toluene dimer. Among these, MDI is particularly desirable. By using MDI, the flexibility of the obtained polyamidoximine resin can be further improved. As an aliphatic diisocyanate such as hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, isophorone diisocyanate. Moreover, aromatic diisocyanate and aliphatic two are used in hydrazine. In the case of an isocyanate, an aliphatic diisocyanate is preferably added in an amount of 5 to 10 mol% to the aromatic diisocyanate, and further use of such an antimony can further improve the polyamidoquinone imide resin. Heat resistance. The resin composition may contain an additive type flame retardant for the purpose of improving flame retardancy. As an additive type flame retardant, it is preferable to use a phosphorus-containing ruthenium charge. For example, OP930 (trade name of Clariant Clariant Company, phosphorus content 23.5%), HCA-HQ (trade name of Sanguang Co., Ltd., phosphorus content 9.6%), PMP-100 of melamine polyphosphate (registered 磷1 4.5 % of phosphorus content) , Ρ Μ P - 2 0 0 (phosphorus content値1 〇 _ 6 % ) and ΡΜΡ-300 (registered 値 12.0% of phosphorus content) (The above is the product name of Nissan Chemical Co., Ltd.) (Metal foil) As the metal foil 1 〇, copper foil and aluminum foil are generally used. The thickness of the metal foil used for the plywood is usually 5 to 200 μm. Further, as the metal foil 10, nickel, nickel-phosphorus, nickel-tin alloy, nickel-iron alloy, lead, lead-tin alloy, or the like may be used. The intermediate layer is provided with a composite film of a three-layer structure of a copper layer of 55 to 15 μm and a copper layer of 10 to 300 μm on both surfaces thereof, or a composite foil of a two-layer structure in which a copper and a copper box are composited. (Metal foil with resin) A metal foil with a resin can be produced by applying the above resin composition to a metal foil 1 to form a resin layer. The above resin layer ' can be obtained, for example, in the following manner. First, the above respective components ' contained in the resin composition are mixed, dissolved, and dispersed in an organic solvent to prepare a resin varnish. As the organic solvent, as long as it is a soluble resin, -18-200904268 may be used, for example, dimethylacetamide, dimethylformamide, dimethylammonium, N-methyl-2-lale can be used. Ketone, γ-butyrolactone, sulfolane, cyclohexanone, methyl ethyl ketone. Coating can be carried out by a conventional method. Specific examples of the coating method include a doctor blade coating method, a die coating method, a lip coating method, and a gravure coating method. As a coating method for forming a resin layer having a predetermined thickness, a die coating method in which a coating material is applied by a doctor blade coating between gaps and a resin varnish having a flow rate adjusted from a nozzle can be used. In the case where the thickness of the resin layer before drying is 50 to 500 μm, it is preferable to use a die coating method. The production conditions of the resin-attached metal foil are not particularly limited, and it is preferred that the organic solvent used for the varnish of the resin composition is volatilized by 80% by mass or more in the resin layer after drying. The drying temperature is about 80 to 180 ° C, and the drying time is determined by taking into consideration the gelation time of the varnish, and is not particularly limited. The coating amount of the resin varnish is preferably such that the thickness of the resin layer after drying is preferably 30 to 70 μm, and more preferably 30 to 50 μm. When the thickness of the resin layer is less than 30 μm, the resin composition tends to be less likely to be embedded in the fiber base material, and when it exceeds 70 μm, the decrease in warpage tends to be difficult. In the case of using a resin-attached metal foil, a laminate obtained by laminating two resin-attached metal foils with a resin surface and a fiber substrate can be formed by heating and press forming. Foil laminate. At this time, the heating temperature is preferably 1 50 to 280 ° C, which is more ideal than 1 80 to 250 ° C. Further, the pressure is preferably 0.5 to 20 MPa, and more preferably 1 to 8 MPa. -19- 200904268 (Resin film) A resin film can be produced by applying a varnish of the above resin composition to a release substrate, drying it, and removing the release substrate. The release substrate is not particularly limited as long as it can withstand the temperature at the time of drying, and a polyethylene terephthalate film, a polyimide film, and a polyamide which are generally used with a release agent can be used. A metal foil such as a film or an aluminum foil with a release agent. The coating of the varnish of the resin composition onto the release substrate can be carried out in the same manner as the above coating method. The drying temperature is in the range of 80 to 180 ° C, and the drying time is determined in consideration of the gelation time of the varnish, and is not particularly limited. The coating amount of the resin varnish is preferably such that the thickness of the obtained resin film is preferably 30 to 70 μm, and more preferably 30 to 50 μm. When the thickness of the resin film is less than 30 μπα, the resin composition tends to be less likely to be embedded in the fiber base material, and when it exceeds 70 μm, the deterioration of warpage tends to be difficult. In the case of using a resin film, a metal foil/resin film/fiber substrate/resin film/metal foil layered laminate is sequentially formed by heating and press forming to form a metal foil-clad laminate. At this time, the heating temperature is preferably 1 50 0 to 2 80 ° C, and more preferably 180 to 250 ° C. Moreover, the pressure is preferably 0.5 to 20 MPa, and more preferably 1 to 8 MPa. The metal foil-clad laminate 200 of the present invention is provided with a fibrous base material layer 4 having a cured product of a fibrous base material and a resin composition embedded in the fibrous base material, and a set of the fibrous base material 4 The laminate 30 of the cured layers 1 and 2 obtained by the cured product of the resin composition and the metal foil 10 of one of the laminates 3'. The difference between the average thickness of the cured layer 1 and the average thickness of the cured layer 2 is -20-200904268, and is preferably 1% or less of the sum of the average thickness of the cured layer 1 and the average thickness of the cured layer 2, More than 5% is more desirable. The average thickness of the cured layer 1 and 2 represents the distance between the average line of the interface between the metal foil 10 and the cured layer 1 and the average line of the interface between the fibrous base material layer and the cured layer 1, and the metal foil 10 The distance between the average line of the interface of the cured layer 2 and the average line of the interface between the fibrous base material layer and the cured product layer 2. When the difference between the average thicknesses of the cured product layers 1 and 2 exceeds 10%, the effect of the present invention which reduces warpage is difficult to exhibit. The thickness of the metal foil-clad laminate 200 produced in this manner is preferably 200 μm or less, more preferably 20 to 180 μm. When the thickness exceeds 200 μm, the flexibility is lowered, and cracking is likely to occur during bending. Moreover, when the thickness is less than 2 Ομηη, the manufacture of the metal foil-clad laminate is very difficult. [Printed wiring board] Fig. 2 is a partial cross-sectional view showing an embodiment of the printed wiring board of the present invention obtained by forming a wiring pattern on the metal foil-clad laminate 200. The printed wiring board 300 shown in Fig. 2 is mainly composed of a wiring pattern 11 formed by the above-described laminate 30 and a metal foil provided on both sides of the laminate 30. Further, a plurality of through holes 70 penetrating the laminate 30 are formed in a direction substantially perpendicular to the principal plane of the laminate 30, and a metal plating layer 60 having a predetermined thickness is formed on the hole walls of the through holes 70. The printed wiring board 300 is obtained by forming the wiring pattern on the metal foil 200. The formation of the line pattern can be performed by a conventional method such as subtraction. Such a printed wiring board 300 is produced by using the metal foil-coated 200904268 laminate of the present invention 20000, and has a small warpage and good flexibility, and can be bent at will. The printed wiring board 300 is suitable for use as a so-called flexible printed wiring board. The present invention has been described in detail based on the embodiments. However, the present invention is not limited to the above embodiment. Various modifications can be made without departing from the scope of the invention. EXAMPLES Hereinafter, preferred embodiments of the present invention will be more specifically described. However, the invention is not limited to the embodiments. (Preparation Example 1) 22.4 kg (solid content 32.2% by mass) of "KS9900B" (manufactured by Hitachi Chemical Co., Ltd.) and "EPPN502H" as epoxy resin (Japanese-made) Pharmacopoeia, product name) 2.0kg (50% by mass of methyl ethyl ketone solution), "HP4032D" (manufactured by Dainippon Ink and Chemicals Co., Ltd., product name) 3.0kg, "NC3000" (Sakamoto Chemical) Company product, trade name) l. 〇 kg (solid content of 50% by mass of methyl ethyl ketone solution), 1-cyanoethyl-2-ethyl-1-imidazole 8.0 g as a curing accelerator. Then, the resin was stirred until it became uniform for about 1 hour, and then left to stand at room temperature (25 ° C) for defoaming for 24 hours to prepare a varnish of the resin composition. (Preparation Example 2) 22.4 kg (solid content: 31.2% by mass) of "KS9900B" (manufactured by Hitachi Chemical Co., Ltd., Ltd., manufactured by Hitachi Chemical Co., Ltd.) as a polyamidoximine. "EPPN502H" (manufactured by Nippon Kayaku Co., Ltd., product name) 2.0kg (methyl ethyl ketone solution of 50% by mass of solid content), "HP4032D" (manufactured by Dainippon Ink and Chemicals, Ltd., product name) 3.0kg, "NC3000" (manufactured by Nippon Kayaku Co., Ltd.), 1.0 kg (100% by mass of methyl ethyl ketone solution), and 1-cyanoethyl-2-ethyl-1-methylimidazole as a hardening accelerator 8.0g', as a phosphorus compound, "Ο P 9 3 0" (manufactured by Klein Co., Ltd., trade name), 1.0 kg, and "HP360" (manufactured by Showa Denko Co., Ltd., trade name) 1.5 kg of aluminum hydroxide. Then, after the resin was made uniform, the mixture was stirred for about 3 hours, and the varnish of the resin composition was prepared for "defoaming" at room temperature (24 ° (:) for 24 hours. (Preparation Example 3) 3.4 kg of "EPICLON 153" (manufactured by Otsuka Ink Chemical Industry Co., Ltd., product name), "FG_2000" (manufactured by Teijin Chemical Co., Ltd., trade name) as a curing agent, 1.81 kg, 1-cyanide as a hardening accelerator Ethyl-2-phenylimidazole 10. 〇g was dissolved in methyl isobutyl ketone (6.0 kg) and added as an acrylic resin "HTR-860-P3" (manufactured by Nagase Chemtex Co., Ltd., trade name) 2_87 kg (solid Ingredients: 15% by mass of methyl ethyl ketone solution) 'Agitating for 1 hour to prepare a varnish of a resin composition. (Formulation Example 4) In addition to blending "BREN-S" (manufactured by Sakamoto Chemical Co., Ltd., trade name) -23- 200904268 3, 3.4kg of EpICLON 153, which is an epoxy resin, is used as a varnish of the resin composition in the same manner as in the mixing example 3. [Examples 1 to 8] <Production of metal foil with resin> Electrolytic copper foil "F2-WS-18" (made by Furukawa Electric Co., Ltd., trade name, Thickness: 1 8 μm), varnish of the resin composition prepared by the preparation example ~4, so that the thickness of each dried resin layer is 30 μm or 50 μm, and is applied by a die coater at 1 0 0 The drying oven of ~1 4 〇t: is heated and dried for 5 minutes with a residence time to obtain a metal foil with resin. <Metal-clad laminate> Prepare a set of the above-mentioned resin-attached metal foil and glass cloth "WEX_ 1 027 (manufactured by Asahi SYUEBEL Co., Ltd., thickness: 19 μη〇, laminated with a resin layer bonded to a glass cloth, and laminated and heated under the conditions shown in Table 1 to produce two-sided copper-clad laminates Laminates. The obtained two-sided copper-clad laminates can be bent at will. [Examples 9 to 12] <Preparation of resin film> Preparation of polyethylene terephthalate film "Α_63" (manufactured by Teijin DuPont Film Co., Ltd. Product name, thickness: 75μηι), as a supporting substrate. The varnish prepared by using Sil groups 1 to 4 on the above-mentioned supporting substrate was coated with a die coater at a thickness of 50 μm after drying. 1〇〇~14〇.(: -24- 200904268 The drying oven is heated and dried for 5 minutes, and the support substrate is peeled off to obtain a resin film. <Metal-clad laminate> Prepare one set of electrolytic copper foil "F 2 - WS -1 8", 1 The resin film and the glass cloth "WEX-1 027" were placed, and then the resin film was placed on both sides of the glass cloth, and the above-mentioned electrolytic copper foil was placed on both sides thereof to be laminated, and heated and added under the conditions shown in Table 1. Pressing, making two-sided copper clad laminates of metal foil-clad laminates. The obtained two-sided copper-clad laminate can be bent at will. [Comparative Examples 1 to 4] <Preparation of Prepreg> The varnish of the resin composition prepared in Examples 1 to 4 was prepared in a glass cloth "WEX-102 7", and the thickness after drying was 60 μm. The coating machine was applied and dried in a drying oven at 1 to 140 ° C for 1 hour in a residence time to obtain a prepreg having a resin component of 70% by mass. <Metal-coated metallized laminate> Electrolytic copper foil F2-WS-18 was placed on both sides of the above-mentioned prepreg, and heated and pressurized under the conditions shown in Table 1, to produce a double-sided copper clad laminate of a metal-clad laminate. [Comparative Examples 5 to 8] In the same manner as in Comparative Examples 1 to 4, the varnish of the resin composition prepared in Examples 1 to 4 was prepared in the glass cloth "WEX-1 027" -25-200904268', and dried. The thickness was 90 μm, and it was coated with a vertical coater, and heated and dried in a drying oven of 1 〇〇 to 丨4 以 for 10 minutes to obtain a resin component of 85 mass%. Prepreg. However, in these prepregs, the drying of the solvent became insufficient, and the metal foil-clad laminate could not be produced. [Appearance of the appearance of the double-sided copper-clad laminate] The warpage of the double-sided copper-clad laminates produced in Examples 1 to 12 and Comparative Examples 1 to 4, and the protrusion of the presence or absence of the fibrous base material were visually evaluated. The results are shown in Table 1. In Table 1, the ◦ indicates that no warpage, swelling, or protrusion of the structure of the fibrous base material occurs, and X means any one of warpage, swelling, and protrusion of the structure of the fibrous base material. -26- 200904268 [Table 1]

Resin composition form forming condition Appearance heating temperature Temperature and pressure time rc/min) (°C) (MPa) (minute) Example 1 Preparation Example 1 Resin copper foil (resin layer: 30 μπ〇5 200 4 60 〇 Example) 2 Preparation Example 2 Resin copper foil (resin layer: 30 μm) 5 200 4 60 〇 Example 3 Preparation Example 3 Resin copper foil (resin layer: 30 μm) 5 185 4 90 〇 Example 4 Preparation example 4 Attached Resin copper foil (resin layer: 30 μm) 5 185 4 90 〇 Example 5 Formulation Example 1 Resin copper foil (resin layer: 50 μm) 5 200 4 60 〇 Example 6 Preparation Example 2 Resin copper foil (resin layer) :50μιη) 5 200 4 60 〇Example 7 Preparation Example 3 Resin copper foil (resin layer: 50 μm) 5 185 4 90 〇 Example 8 Preparation Example 4 Resin copper foil (resin layer: 50 μπ〇5 185 4) 90 〇 Example 9 Preparation Example 11 Resin film 5 200 4 60 〇 Example 1 〇 Formulation 2 Resin film 5 200 4 60 〇 Example 11 Preparation Example 3 Resin film 5 185 4 90 〇 Example 12 Preparation Example 4 Resin film 5 185 4 90 〇Comparative example 1 Preparation example 11 Blending Example 2 5 200 4 60 X Comparative Example 2 prepreg 5 200 4 60 X Comparative Example 3 Blending Example dip 5 185 4 90 X Comparative Example 4 Example 4 formulation prepreg prepreg 3 5 185 4 90 X

[Measurement of Warpage] The two-sided copper-clad laminates produced in Examples 1 to 1 and Comparative Examples 1 to 4 were cut to have a width of 100 mm and a length of 200 mm, and a 10 mm portion was measured from the end portion by a warpage gauge. the height of. Further, the copper of the double-sided copper clad laminate is removed by etching to form a resin sheet. The curl of the resin sheet and the presence or absence of waves were visually observed. Further, in the case where the resin sheet was flat, warpage was measured by a warpage gauge. The results are shown in Table 2. -27- 200904268 [Sectional observation of the double-sided copper-clad laminate] The cross-sections of the two surfaces produced in Examples 1 to 2 and Comparative Examples 1 to 4 were observed under a microscope. As shown in Fig. 2, the hardening of the two resin compositions existing between the fiber and the copper foil 1 , is measured from the interval between the average lines between the interfaces, and the two cured layers are respectively measured. The thicker one is the hardened layer 2 which is harder. Then, the ratio of the difference in the average thickness of the object layers 1 and 2 is expressed by the following formula (1). The result indicates the ratio (%) of the difference in the average thickness of the J hardened layer =

Average thickness of 1 - average thickness of hardened layer 2) / (hard f average thickness + average thickness of hardened layer 2) x100

[Evaluation of heat resistance] (Normal solder heat resistance) On both surfaces prepared in Examples 1 to 12 and Comparative Examples 1 to 4, 5 cm square was cut out as a sample for measurement. Sample for measurement The presence or absence of deformation such as floating and expansion in the solder bath is visually observed: the maximum is 300 seconds. The results are shown in Table 2. (Heat-absorbing solder heat resistance) In each of the two surfaces produced in Examples 1 to 1 and Comparative Examples 1 to 4, 5 cm square was cut out, and the copper foil on one side was removed by etching, and the tester (condition: 121 ° C, 2 atm) ) 1 hour' sample. The measurement sample was immersed in a solder bath at 288 ° C for 20 seconds. The copper-clad laminate was used to maintain the thickness of the substrate layers 1 and 2 . And the layer 1, and the hardening i order table 2 is calculated. (The cured layer of the layer 1 (1) The copper-clad laminate was observed at 260 °. During the measurement, the copper-clad laminate was placed in a pressure cooker for measurement, and after taking out, the presence or absence of deformation such as expansion was visually observed at -28-200904268. The results are shown in Table 2. Further, in Table 2, the lanthanum refers to deformation such as swelling, and the x system refers to no deformation. [Table 2]

Laminate-coated metal foil resin sheet solder heat-resistant laminate cured layer 1 hardened layer 2 ratio of thickness difference warpage amount curl _ volume normal moisture absorption (μπι) (μπι) (%) (mm) (mm Example 1 26 26 〇0 No 0 〇〇Example 2 29 28 1 75 No 0 〇〇Example 3 28 26 3 70 No 0 〇〇Example 4 26 25 1.96 0 No 0 〇〇Example 5 49 48 1 〇3 None Example 6 49 47 2.08 2 _ No 2 〇〇 Example 7 45 44 1 12 0 No 0 〇〇 Example 8 46 44 2.22 4af. No 0 〇〇Example 9 49 49 〇0 1 None 0 〇〇Example 10 49 47 2.08 2 int. Innocent Example 11 46 43 3.37 1 No 0 〇〇 Example 12 44 43 1.15 0 No 0 〇〇Comparative Example 1 1 24 19 11.63 5 Yes (large) -t X - This Comparative Example 2 25 19 13 64 8 Yes (Large) • t X Comparative Example 3 28 21 14.29 3 Yes (small) 1 XX Comparative Example 4 25 20 11.11 2 Yes (small) 1 XX * Curl is large It is impossible to evaluate the double-sided copper-clad laminates of Examples 1 to 8 obtained by laminating a metal foil with a resin and a glass cloth, and the cured layer thereof 〇~3 ratio of difference in thickness and 70% 'is also the maximum warpage even 2mm or less, good solder heat resistance is good. The copper of any two-side copper clad laminate is etched, and the resin sheet is not curled. -29-200904268 Two-side copper clad laminate of Examples 9 to 12 obtained by laminating a resin film, a glass cloth and a copper foil, and a cured product thereof The ratio of the thickness difference of the layers is 0 to 3.3 7%, and the warpage is also 2 mm or less at the maximum, and the solder heat resistance is also good. The copper of any two-side copper-clad laminate was etched, and the resin plate was not crimped. The two-side copper-clad laminate of Comparative Examples 1 to 4 obtained by laminating the prepreg and the copper foil had a difference in thickness of the cured layer. The part with a ratio of more than 10% has a warp of 2 to 5 mm, and the solder has insufficient heat resistance. When the copper of these two-sided copper clad laminates is etched, the curl of the resin sheet can be seen. Further, as shown below, the thickness of the fiber base material and the thickness of the resin layer of the resin-attached copper foil were changed, and the double-sided copper clad laminates of Examples 13 to 27 and Comparative Examples 9 to 14 were produced and evaluated. The results are shown in Table 3. [Example 1 3 to 1 5 ] The glass cloth "WEX-1 027" was changed into a glass cloth "WEX-1017" (manufactured by Asahi SYUEBEL Co., Ltd., thickness: 13 μηι), and two sides of a copper foil with resin attached were prepared as described above. Copper laminate. The obtained double-sided copper-clad laminate can be bent at will. [Examples 16 to 21] The glass cloth "WEX-1 027" was changed into a glass cloth "WEX-1037" (manufactured by Asahi SYUEBEL Co., Ltd., thickness: 50 μηι), and two sides of a copper box with a resin attached thereto were prepared as described above. Copper laminate. The obtained double-sided copper-clad laminate can be bent at will. -30-200904268 [Example 2 2 to 2 7 ] Glass cloth "WEX-1027" was changed into glass; Asahi SYUEBEL Co., Ltd., thickness: 50 μηι), copper-clad laminate on both sides of resin copper foil. The results can be bent at will. [Comparative Example 9 to 1 1] The glass cloth "W Ε X - 1 0 2 7" was changed into glass; i Asahi SYUEBEL Co., Ltd., thickness: 70 μη〇 ' Both sides of a copper foil with a resin copper clad laminate. However, it is not fully embedded and cannot be evaluated. [Comparative Example 1 2 to 1 4] The glass cloth "WEX-1 027" was changed to a glass cloth (manufactured by Tosoh Corporation, thickness: ΙΟΟμηη), and the copper foil of both sides of the above copper foil was laminated. However, the tree is insufficient and cannot be evaluated. [J "WEX- 1 0 86" (If the above-mentioned production uses the two-sided copper-clad laminate ί "WEX-33 1 3" (as used in the above-mentioned production, resin-to-glass cloth GA-70 1 0" (denotation) Preparation using a resin-impregnated glass cloth -31 - 200904268 [Table 3] Resin composition resin layer thickness (μπ〇 fiber base material thickness (μιη) molding condition appearance solder heat resistance temperature increase temperature (t/min) Temperature CC) Pressure (MPa) Time (minutes) After normal moisture absorption Example 13 Formulation Example 1 50 13 5 200 4 60 〇〇〇 Example 14 Preparation Example 2 50 13 5 200 4 60 〇〇〇 Example 15 Preparation Example 3 50 13 5 1B5 4 90 〇〇〇 Example 16 Preparation Example 1 40 28 5 200 4 60 〇〇〇 Example 17 Preparation Example 2 40 28 5 200 4 60 〇〇〇 Example 18 Preparation Example 3 40 28 5 185 4 90 〇〇〇 Example 19 Formulation Example 1 50 28 5 200 4 60 〇〇〇 Example 20 Preparation Example 2 50 28 5 200 4 60 〇〇〇 Example 21 Preparation Example 3 50 28 5 185 4 90 〇〇〇 Example 22 Formulation Example I 50 50 5 200 4 60 〇〇〇 Example 23 Preparation Example 2 50 50 5 200 4 60 〇〇〇 Example 24 Formulation Example 3 50 50 5 185 4 90 〇〇〇 Example 25 Preparation Example 1 70 50 5 200 4 60 〇〇〇 Example 26 Preparation Example 2 70 50 5 200 4 60 〇〇〇 Example 27 Formulation Example 3 70 50 5 185 4 90 〇〇〇 Comparative Example 9 Example 1 90 70 5 200 4 60 XX - Wood Comparative Example 10 Formulation Example 2 90 70 5 200 4 60 〇X - Wood Comparative Example 11 Preparation Example 3 90 70 5 185 4 90 〇〇X Comparative Example Preparation Example 1 90 100 5 200 4 60 XX - Wood Comparative Example 13 Preparation Example 2 90 100 5 200 4 60 XX - Wood Comparative Example 14 Preparation Example 3 90 100 5 185 4 90 XX - wood * curled large and could not be evaluated even if the thickness of the fiber substrate and the thickness of the resin layer were changed, the two-side copper-clad laminate of Example 13 to 27, the occurrence of warpage can sufficiently reduce the solder heat resistance. Also good, the resin plate after the copper was etched was not curled. The metal foil-clad laminate of the present invention and the printed wiring board ‘ using the same can be bent in any state in any state, and the frame on which the printed wiring board is mounted can be audibly densely collected. Industrial Applicability According to the present invention, it is possible to provide a metal foil-clad laminate which can produce a printed wiring board which is excellent in heat resistance, sufficiently reduces warpage, and which can be bent at will, and a printed wiring board using the same. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a partial cross-sectional view showing an embodiment of a metal foil-clad laminate according to the present invention. Fig. 2 is a partial cross-sectional view showing an embodiment of a printed wiring board according to the present invention. [Main component symbol description] 1 : Hardened layer 2 : Hardened layer 4 : Fiber base material layer 1 0 : Metal vane 3 0 : Laminate 1 1 : Circuit pattern 60 : Metal plating layer 7 0 : Through hole 200 : Metal foil laminated board 3 0 0 : Printed circuit board -33-

Claims (1)

200904268 X. Patent Application Area 1. A metal foil-clad laminate, characterized in that a fiber substrate having a glass cloth having a thickness of 50 μm or less is provided with a metal foil and formed on the metal foil via heating Further, a resin-attached metal foil of a resin layer obtained by curing the resin composition is disposed such that the resin layer is bonded to the fiber base material, and is heated and pressurized to form an integrated product. 2. The metal foil-clad laminate according to claim 1, wherein the resin layer has a thickness of 30 to 70 μm. 3. The metal foil-clad laminate according to the first aspect of the invention, comprising: a fibrous base material layer obtained from the fibrous base material and a cured product of the resin composition embedded in the fibrous base material; a laminate of a cured layer of a group obtained by sandwiching a cured product of the foregoing resin composition of the fibrous base material layer with a metal foil-clad laminate of a metal foil of a group of the laminate, wherein The difference in average thickness of the cured layer of the aforementioned group is 10% or less of the total thickness of the cured layer of the aforementioned one set. 4. The metal foil-clad laminate according to claim 1, wherein the resin composition contains a thermosetting resin. 5. The metal foil-clad laminate according to item 4 of the patent application, wherein the thermosetting resin is an epoxy resin. A metal foil-clad laminate according to the first aspect of the invention, wherein the resin composition contains a polyamidoximine resin. 7. The metal foil-clad laminate according to claim 1, wherein the resin composition contains an acrylic resin. 8. A metal foil-clad laminate, characterized in that a fiber substrate having a glass cloth having a thickness of 50 μm or less and a resin composition which is disposed on both sides of the fiber substrate and cured by heating One of the obtained resin films is integrated with a metal foil disposed on the opposite side of the fiber substrate of the resin film by heating and pressurization. 9. The metal foil-clad laminate according to claim 8, wherein the resin film has a thickness of 30 to 70 μm. A metal foil-clad laminate according to claim 8 which is provided with a fibrous base material layer obtained from the fibrous base material and a cured product of the resin composition embedded in the fibrous base material a laminate of a cured layer of a set of a cured product of the resin composition of the fibrous base material layer, and a metal foil-clad laminate of a metal foil of a group of the laminate The difference in average thickness of the cured layer of the aforementioned one set is less than 1% by weight of the total thickness of the cured layer of the aforementioned one set. 11. The metal foil-clad laminate according to item 8 of the patent application, wherein -35-200904268 the resin composition contains a thermosetting resin. The metal foil-clad laminate according to the first aspect of the invention, wherein the thermosetting resin is an epoxy resin. The metal foil-clad laminate according to claim 8, wherein the resin composition contains a polyamidoximine resin. The metal foil-clad laminate according to claim 8, wherein the resin composition contains an acrylic resin. A printed wiring board characterized by forming a wiring pattern on a metal foil-clad laminate according to any one of claims 1 to 4 of the patent application. -36-